# S/PDIF not working properly. Help? **URL:** \ **Category:** Factual Questions\ **Created:** [July 17, 2010, 6:14am UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999 "2010-07-17T06:14:18Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Rex\_Goliath](https://avatars.discourse-cdn.com/v4/letter/r/bcef8e/32.png) [@Rex\_Goliath](https://boards.straightdope.com/u/Rex_Goliath)\ **Post date:** [July 17, 2010, 6:14am UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/1 "2010-07-17T06:14:18Z")
Running Windows 7, with a SoundBlaster SE installed. It has a [digital out](http://c1.neweggimages.com/BizIntell/item/29/102/29-102-002/29-102-002_1.jpg) port. I’m running a 3.5mm-\>TOSLINK cable straight into my receiver, but receiving no audio. The card works correctly, as I can still get analog sound with a 3.5mm-\>RCA adapter. I’ve disabled all other sound devices in the device manager, ensured my receiver was set to the proper configuration, etc. What am I missing here? ---
**Author:** ![Harmonious\_Discord](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@Harmonious\_Discord](https://boards.straightdope.com/u/Harmonious_Discord)\ **Post date:** [July 17, 2010, 10:15am UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/2 "2010-07-17T10:15:29Z")
See what bit rate your receiver takes. You’re probably sending a signal that is at the wrong bit rate. This assumes you have already checked that the digital out is turned on in the audio software and also not muted in the mixer software. ---
**Author:** ![Rex\_Goliath](https://avatars.discourse-cdn.com/v4/letter/r/bcef8e/32.png) [@Rex\_Goliath](https://boards.straightdope.com/u/Rex_Goliath)\ **Post date:** [July 17, 2010, 4:34pm UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/3 "2010-07-17T16:34:51Z")
I checked that, it’s set to the same frequency. Since I posted this, I’ve done a little bit of experimenting, and suspect that it may be my receiver that is dying. Bummer. ---
**Author:** ![sharding](https://avatars.discourse-cdn.com/v4/letter/s/90db22/32.png) [@sharding](https://boards.straightdope.com/u/sharding)\ **Post date:** [July 17, 2010, 4:57pm UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/4 "2010-07-17T16:57:47Z")
Is it actually lighting up the fiber? ---
**Author:** ![Rex\_Goliath](https://avatars.discourse-cdn.com/v4/letter/r/bcef8e/32.png) [@Rex\_Goliath](https://boards.straightdope.com/u/Rex_Goliath)\ **Post date:** [July 18, 2010, 5:08pm UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/5 "2010-07-18T17:08:57Z")
There’s no fiber to light up in this scenario, since it’s a simple 3.5" digital out. It’s a simple cable conversion to TOSLINK that makes it work. The audio works from my Macbook, but further research has shown that only Apple computers come with the ability to run a 3.5"-\>toslink built in. > **[Phone connector (audio) | Computer sound](https://en.wikipedia.org/wiki/TRS_connector#Computer_sound)** > > Any number of 3.5 mm sockets for input and output may be found on personal computers, either from integrated sound hardware common on motherboards or from insertable sound cards. The 1999 PC System Design Guide's color code for 3.5 mm TRS sockets is common, which assigns pink for microphone, light blue for line in, and lime for line level. AC'97 and its 2004 successor Intel High Definition Audio have been widely adopted specifications that, while not mandating physical sockets, do provide specifi... I did more digging, and it seems the SoundBlaster won’t deliver the proper signal without purchasing a second product, some sort of external digital I/O box. I never suspected that digital passthrough could be this complicated. This should be the _easiest_ thing for a sound card to do. It’s doing _zero_ work. > [@Harmonious\_Discord](#): > > See what bit rate your receiver takes. You’re probably sending a signal that is at the wrong bit rate. This assumes you have already checked that the digital out is turned on in the audio software and also not muted in the mixer software. I got to thinking about this, and went to try my old TurtleBeach sound card which never worked, even though it had a traditional Optical port. This one is at the wrong frequency, explaining why it didn’t work. _sigh_ Now for my third sound card. Fingers crossed. ---
**Author:** ![sharding](https://avatars.discourse-cdn.com/v4/letter/s/90db22/32.png) [@sharding](https://boards.straightdope.com/u/sharding)\ **Post date:** [July 18, 2010, 5:18pm UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/6 "2010-07-18T17:18:05Z")
> [@Rex\_Goliath](#): > > There’s no fiber to light up in this scenario, since it’s a simple 3.5" digital out. It’s a simple cable conversion to TOSLINK that makes it work. Sorry, I’m confused. TOSLINK is basically just a piece of optical fiber. You need something to send the digital signals as light down that fiber for it to work; you can’t just do a physical connector change. If it’s not an optical digital out, what is it? Is it supposed to be for coaxial S/PDIF (rather than optical, which is what TOSLINK is)? TOSLINK is not the only kind of S/PDIF. Anyway, sounds like you have it figured out, but I’m still kind of curious. I’m definitely not up to speed on PC sound cards, so it’s definitely possible there’s something I’m missing here. ---
**Author:** ![Rex\_Goliath](https://avatars.discourse-cdn.com/v4/letter/r/bcef8e/32.png) [@Rex\_Goliath](https://boards.straightdope.com/u/Rex_Goliath)\ **Post date:** [July 18, 2010, 5:26pm UTC](https://boards.straightdope.com/t/s-pdif-not-working-properly-help/546999/7 "2010-07-18T17:26:44Z")
My mistake. It is a fiber optic cable, but so durned tiny that I thought it was a simple copper wire. On my macbook, it doesn’t put out the red light unless audio is actively playing, which I never knew. Learn something new every day.